The present invention relates to test-gas leak detectors.
A leak detector is known from the publication DE 31 24 205 A1. It comprises a high-vacuum pump designed by way of a turbomolecular pump to the inlet of which a test-gas detector is connected, as well as a forevacuum pump. Moreover, the high-vacuum pump is equipped with an intermediate inlet and an outlet. Connected to these connections is a system of conduits which besides the conduits exhibits valves and connections for a device under test and for the forevacuum pump. The components stated are arranged such that the device under test is linked through a first valve to the intermediate inlet of the high-vacuum pump. Moreover, the device under test is connected through a second valve to the inlet of the forevacuum pump. Finally, also the outlet of the high-vacuum pump is connected through a third valve to the inlet of the forevacuum pump.
The construction of the known test-gas leak detector is involved since it consists of a multitude of individual components. Disadvantageous is, moreover, the adaptation of the properties of the test-gas leak detectors to differing leak search methods or devices under test. To this end the high-vacuum pump needs to be replaced by a different type having properties which are adapted to the changed circumstances. This requires that the system of conduits and valves and the test-gas detector be separated from the connections of the high-vacuum pump and thereafter be connected to the connections of the new high-vacuum pump in a vacuum-tight manner. This complexity is all the greater the more intermediate connections the high-vacuum pump has. From U.S. Pat. No. 5,561,240, it is known to equip the high-vacuum pump with several intermediate connections. Embodiments of this kind are lately being used evermore frequently.